428 lines
12 KiB
Groff
428 lines
12 KiB
Groff
.\" $OpenBSD: mount.8,v 1.90 2019/03/10 14:42:21 schwarze Exp $
|
|
.\" $NetBSD: mount.8,v 1.11 1995/07/12 06:23:21 cgd Exp $
|
|
.\"
|
|
.\" Copyright (c) 1980, 1989, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)mount.8 8.7 (Berkeley) 3/27/94
|
|
.\"
|
|
.Dd $Mdocdate: March 10 2019 $
|
|
.Dt MOUNT 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm mount
|
|
.Nd mount file systems
|
|
.Sh SYNOPSIS
|
|
.Nm mount
|
|
.Op Fl AadfNruvw
|
|
.Op Fl t Ar type
|
|
.Nm mount
|
|
.Op Fl dfrsuvw
|
|
.Ar special | node
|
|
.Nm mount
|
|
.Op Fl dfruvw
|
|
.Op Fl o Ar options
|
|
.Op Fl t Ar type
|
|
.Ar special node
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
command invokes a file system specific program to prepare
|
|
and graft the
|
|
.Ar special
|
|
device or remote node (rhost:path) on to the file system
|
|
tree at the point
|
|
.Ar node .
|
|
If either
|
|
.Ar special
|
|
or
|
|
.Ar node
|
|
are not provided, the appropriate information is taken from the
|
|
.Xr fstab 5
|
|
file.
|
|
.Pp
|
|
For disk partitions, the
|
|
.Ar special
|
|
device is either a
|
|
.Xr disklabel 8
|
|
UID (DUID) or an entry in
|
|
.Pa /dev .
|
|
If it is a DUID,
|
|
it will be automatically mapped to the appropriate entry in
|
|
.Pa /dev .
|
|
In either case the partition must be present
|
|
in the disklabel loaded from the device.
|
|
The partition name is the last letter in the entry name.
|
|
For example, /dev/sd0a and 3eb7f9da875cb9ee.a both refer to the
|
|
.Sq a
|
|
partition.
|
|
.Pp
|
|
A mount point
|
|
.Ar node
|
|
must be an existing directory for a mount to succeed
|
|
.Po
|
|
except in the special case of
|
|
.Pa / ,
|
|
of course
|
|
.Pc .
|
|
Only the superuser may mount file systems.
|
|
.Pp
|
|
The system maintains a list of currently mounted file systems.
|
|
If no arguments are given to
|
|
.Nm mount ,
|
|
this list is printed.
|
|
.Pp
|
|
The options are as follows:
|
|
.Bl -tag -width Ds
|
|
.It Fl A
|
|
Causes
|
|
.Nm
|
|
to try to mount all of the file systems listed in the
|
|
.Xr fstab 5
|
|
table except those for which the
|
|
.Dq noauto
|
|
or
|
|
.Dq net
|
|
options are specified.
|
|
.It Fl a
|
|
Similar to the
|
|
.Fl A
|
|
flag, except that if a file system (other than the root file system)
|
|
appears to be already mounted,
|
|
.Nm
|
|
will not try to mount it again.
|
|
.Nm
|
|
assumes that a file system is already mounted if a file system with
|
|
the same type is mounted on the given mount point.
|
|
More stringent checks are not possible because some file system types
|
|
report strange values for the mounted-from device for mounted file
|
|
systems.
|
|
.It Fl d
|
|
Causes everything to be done except for the invocation of
|
|
the file system specific program.
|
|
This option is useful in conjunction with the
|
|
.Fl v
|
|
flag to
|
|
determine what the
|
|
.Nm
|
|
command is trying to do.
|
|
.It Fl f
|
|
Either force mounting of dirty file systems or, in the case of a
|
|
downgrade from read-write to read-only operation, the revocation of
|
|
opened files with write access.
|
|
.It Fl N
|
|
If used with either
|
|
.Fl A
|
|
or
|
|
.Fl a ,
|
|
.Nm
|
|
will only look at file systems which have the
|
|
.Dq net
|
|
option specified.
|
|
By default file systems with the
|
|
.Dq net
|
|
option are ignored.
|
|
.It Fl o Ar options
|
|
Options can be given with (or without) a
|
|
.Sq no
|
|
prefix to invert their meaning.
|
|
The options listed below specify non-default values.
|
|
For example,
|
|
.Sq nosoftdep
|
|
is the default, so
|
|
.Sq softdep
|
|
can be used to mount the file system using soft dependencies.
|
|
Multiple options can be specified in a comma-separated list.
|
|
The available options are as follows:
|
|
.Bl -tag -width 9n
|
|
.It Cm async
|
|
Metadata I/O to the file system should be done asynchronously.
|
|
By default, only regular data is read/written asynchronously.
|
|
.Pp
|
|
This is a
|
|
.Em dangerous
|
|
flag to set since it does not guarantee to keep a consistent
|
|
file system structure on the disk.
|
|
You should not use this flag
|
|
unless you are prepared to recreate the file system should your
|
|
system crash.
|
|
The most common use of this flag is to speed up
|
|
.Xr restore 8
|
|
where it can give a factor of two speed increase.
|
|
.Pp
|
|
The options
|
|
.Ic async
|
|
and
|
|
.Ic softdep
|
|
are mutually exclusive.
|
|
.It Cm force
|
|
The same as
|
|
.Fl f ;
|
|
forces the revocation of write access when trying to downgrade
|
|
a file system mount status from read-write to read-only.
|
|
.It Cm noatime
|
|
Do not update atime on files in the system unless the mtime or ctime
|
|
is being changed as well.
|
|
This option is useful for laptops and news servers where one does
|
|
not want the extra disk activity associated with updating the atime.
|
|
.It Cm nodev
|
|
Do not interpret character or block special devices on the file system.
|
|
This option is useful for a server that has file systems containing
|
|
special devices for architectures other than its own.
|
|
.It Cm noexec
|
|
Do not allow execution of any binaries on the mounted file system.
|
|
This option is useful for a server that has file systems containing
|
|
binaries for architectures other than its own.
|
|
.It Cm noperm
|
|
(FFS only)
|
|
Do not check permissions when creating, accessing or modifying files and
|
|
directories in the mounted file system.
|
|
This allows unprivileged users to construct a file hierarchy containing
|
|
special device nodes and files with arbitrary file mode, owner or group
|
|
without restriction.
|
|
Only the owner, group and mode of the root directory of the filesystem
|
|
will be honored so access to the filesystem can be locked down.
|
|
The noperm option also enables the nodev and noexec options to ensure
|
|
that interpretation of the file modes and special devices cannot be
|
|
used to gain privileges.
|
|
.It Cm norw
|
|
An alias for rdonly.
|
|
.It Cm nosuid
|
|
Do not allow set-user-identifier or set-group-identifier bits to take effect.
|
|
.It Cm rdonly
|
|
The same as
|
|
.Fl r ;
|
|
mount the file system read-only (even the superuser may not write it).
|
|
.It Cm ro
|
|
An alias for rdonly.
|
|
.It Cm softdep
|
|
(FFS only)
|
|
Mount the file system using soft dependencies.
|
|
Instead of metadata being written immediately, it is written in an ordered
|
|
fashion to keep the on-disk state of the file system consistent.
|
|
This results in significant speedups for file create/delete operations.
|
|
This option is ignored when using the
|
|
.Fl u
|
|
flag and a file system is already mounted read/write.
|
|
.Pp
|
|
The options
|
|
.Ic async
|
|
and
|
|
.Ic softdep
|
|
are mutually exclusive.
|
|
.It Cm sync
|
|
Regular data I/O to the file system should be done synchronously.
|
|
By default, only metadata is read/written synchronously.
|
|
.It Cm update
|
|
The same as
|
|
.Fl u ;
|
|
indicate that the status of an already mounted file system should be changed.
|
|
.It Cm wxallowed
|
|
Processes that ask for memory to be made writeable plus executable
|
|
using the
|
|
.Xr mmap 2
|
|
and
|
|
.Xr mprotect 2
|
|
system calls are killed by default.
|
|
This option allows those processes to continue operation.
|
|
It is typically used on the
|
|
.Pa /usr/local
|
|
filesystem.
|
|
.El
|
|
.Pp
|
|
Any additional options specific to a given file system type (see the
|
|
.Fl t
|
|
option) may be passed as a comma separated list; these options are
|
|
distinguished by a leading
|
|
.Dq \&-
|
|
(dash).
|
|
Options that take a value are specified using the syntax -option=value.
|
|
For example:
|
|
.Bd -literal -offset 3n
|
|
# mount -t mfs -o rw,nodev,nosuid,-s=153600 /dev/sd0b /tmp
|
|
.Ed
|
|
.Pp
|
|
That causes
|
|
.Nm
|
|
to execute the equivalent of:
|
|
.Bd -literal -offset 3n
|
|
# /sbin/mount_mfs -o rw,nodev,nosuid -s 153600 /dev/sd0b /tmp
|
|
.Ed
|
|
.Pp
|
|
The equivalent example in
|
|
.Xr fstab 5
|
|
would be:
|
|
.Bd -literal -offset 3n
|
|
swap /tmp mfs rw,nodev,nosuid,-s=153600 0 0
|
|
.Ed
|
|
.It Fl r
|
|
The file system is to be mounted read-only.
|
|
Mount the file system read-only (even the superuser may not write it).
|
|
The same as the
|
|
.Dq rdonly
|
|
argument to the
|
|
.Fl o
|
|
option.
|
|
.It Fl s
|
|
Skip mounting the file system if it is already mounted.
|
|
See the
|
|
.Fl a
|
|
flag for a description of the criteria used to decide if a file system
|
|
is already mounted.
|
|
.It Fl t Ar type
|
|
The argument following the
|
|
.Fl t
|
|
is used to indicate the file system type.
|
|
The type
|
|
.Ar ffs
|
|
is the default.
|
|
The
|
|
.Fl t
|
|
option can be used
|
|
to indicate that the actions should only be taken on
|
|
file systems of the specified type.
|
|
More than one type may be specified in a comma separated list.
|
|
The list of file system types can be prefixed with
|
|
.Dq no
|
|
to specify the file system types for which action should
|
|
.Em not
|
|
be taken.
|
|
For example, the
|
|
.Nm
|
|
command:
|
|
.Bd -literal -offset indent
|
|
# mount -a -t nonfs,mfs
|
|
.Ed
|
|
.Pp
|
|
mounts all file systems except those of type NFS and MFS.
|
|
.Pp
|
|
.Nm
|
|
will attempt to execute a program in
|
|
.Pa /sbin/mount_ Ns Em XXX
|
|
where
|
|
.Em XXX
|
|
is replaced by the type name.
|
|
For example, NFS file systems are mounted by the program
|
|
.Pa /sbin/mount_nfs .
|
|
.It Fl u
|
|
The
|
|
.Fl u
|
|
flag indicates that the status of an already mounted file
|
|
system should be changed.
|
|
Any of the options discussed above (the
|
|
.Fl o
|
|
option)
|
|
may be changed;
|
|
also a file system can be changed from read-only to read-write
|
|
or vice versa.
|
|
An attempt to change from read-write to read-only will fail if any
|
|
files on the file system are currently open for writing unless the
|
|
.Fl f
|
|
flag is also specified.
|
|
Only options specified on the command line with
|
|
.Fl o
|
|
are changed;
|
|
other file system options are unaltered.
|
|
The options set in the
|
|
.Xr fstab 5
|
|
table are ignored.
|
|
.It Fl v
|
|
Verbose mode.
|
|
.It Fl w
|
|
The file system object is to be read and write.
|
|
.El
|
|
.Pp
|
|
The options specific to the various file system types are
|
|
described in the manual pages for those file systems'
|
|
.Nm mount_XXX
|
|
commands.
|
|
For instance, the options specific to Berkeley
|
|
Fast File Systems are described in the
|
|
.Xr mount_ffs 8
|
|
manual page.
|
|
.Sh FILES
|
|
.Bl -tag -width /etc/fstab -compact
|
|
.It Pa /etc/fstab
|
|
file system table
|
|
.El
|
|
.Sh EXAMPLES
|
|
Mount a CD-ROM on node
|
|
.Pa /mnt/cdrom :
|
|
.Pp
|
|
.Dl # mount -t cd9660 -r /dev/cd0a /mnt/cdrom
|
|
.Pp
|
|
Mount an MS-DOS USB stick with DUID 3eb7f9da875cb9ee on node
|
|
.Pa /mnt/key :
|
|
.Pp
|
|
.Dl # mount -t msdos 3eb7f9da875cb9ee.i /mnt/key
|
|
.Pp
|
|
Graft a remote NFS file system on host
|
|
.Ar host ,
|
|
path
|
|
.Pa /path/name ,
|
|
on node
|
|
.Pa /mnt/nfs :
|
|
.Pp
|
|
.Dl # mount host:/path/name /mnt/nfs
|
|
.Pp
|
|
Remount
|
|
.Pa /var
|
|
with option
|
|
.Dq dev :
|
|
.Pp
|
|
.Dl # mount -u -o dev /var
|
|
.Sh SEE ALSO
|
|
.Xr mount 2 ,
|
|
.Xr fstab 5 ,
|
|
.Xr disklabel 8 ,
|
|
.Xr mount_cd9660 8 ,
|
|
.Xr mount_ext2fs 8 ,
|
|
.Xr mount_ffs 8 ,
|
|
.Xr mount_mfs 8 ,
|
|
.Xr mount_msdos 8 ,
|
|
.Xr mount_nfs 8 ,
|
|
.Xr mount_ntfs 8 ,
|
|
.Xr mount_tmpfs 8 ,
|
|
.Xr mount_udf 8 ,
|
|
.Xr mount_vnd 8 ,
|
|
.Xr sysctl 8 ,
|
|
.Xr umount 8
|
|
.Sh HISTORY
|
|
A
|
|
.Nm
|
|
command appeared in
|
|
.At v1 .
|
|
.Sh CAVEATS
|
|
After a successful
|
|
.Nm mount ,
|
|
the permissions on the original mount point determine if
|
|
.Dq \&.\&.
|
|
is accessible from the mounted file system.
|
|
The minimum permissions for
|
|
the mount point for traversal across the mount point in both
|
|
directions to be possible for all users is 0111 (execute for all).
|